.nav {
    border: 1px solid #e2e3e5;
    padding: 2em 10em;
}

.nav button {
    padding: 5px 20px;
}

.pre_devices_list {
    border: 1px solid #e2e3e5;
    background: #e9eaea;
    padding: 10px 20px;
    font-size: 16px;
    font-family: sans-serif;
    line-height: 1.8em;
}